1992, Rudolf M. Schuster, The Hepaticae and Anthocerotae of North America: East of the Hundredth Meridian, volume V, page 6

The Chilean Amphijubula Schust. (Schuster, 1970a) which has the facies of a small Frullania and agrees with Frullania in leaf insertion and branching, has a nontiered seta with 16 epidermal cell rows surrounding 4 inner rows.